Natural products (NPs) continue to play an important role for the discovery of new therapeutic candidates. Over the past 30 years, NPs or their derivatives have accounted for 60% of new anticancer agents and almost 75% of all new antibacterial molecules [1-3]. One hundred NP and NP-derived substances were being evaluated in clinical trials or were being registered at the end of 2013 [4]. NPs have been isolated from many terrestrial and marine organisms, including plants, marine invertebrates, and microorganisms, the latter being the source selected more often for pharmaceutical drug discovery programs. Microorganisms (traditionally actinobacteria and fungi, but more recently cyanobacteria and myxobacteria as well) are one of the most prolific sources among living organisms for the production of bioactive molecules. Exploitation of their specialized (commonly termed secondary) metabolism has guaranteed for decades already the discovery of novel antibiotics and other compounds with unprecedented chemical characteristics and biological properties not existing in screening libraries of synthetic compounds [1,5]. Querying the literature, we previously reported [6,7] that among more than 31600 microbial products discovered from 1900 onwards, ca. 20200 possess some biological activity. Among them 35% were produced from filamentous fungi, 48% from actinomycetes, and 17% from other bacteria. According to Berdy [2] ca. 20000 and 22000 bioactive microbial secondary metabolites had been described in the scientific and patent literature by the end of 2000 and 2002, respectively. About 38% of these molecules are produced by filamentous fungi, whereas the largest group (45%) derives from actinomycetes (7600 metabolites from Streptomyces and 2500 from the so-called rare filamentous actinomycetes). The remaining 17% is produced by other bacteria such as Bacillus, Pseudomonas, myxobacteria, and cyanobacteria. During the past 15 years, we have registered the proJOURNAL OF APPLIED BIOANALYSIS, Apr. 2015, p. 55-67. http://dx.doi.org/10.17145/jab.15.010 Vol. 1, No. 2